A new fluorescence chemosensor based on benzothiazole derivative for Zn2+ and its logic gate behavior

A novel benzothiazole derivative J as a fluorescent chemosensor for Zn²⁺ has been designed and synthesized. The chemosensor J exhibits high selectivity and sensitivity to Zn²⁺ as fluorescence “turn-on” behavior, which the other cations do not make sense. The detection limit calculated by fluorescence titration method was 1.64 × 10^?8 M. Furthermore, the generated J-Zn²⁺ ensemble could recover the enhanced fluorescence upon the addition of EDTA generating an “on-off-on” recycle. In addition, the test strip based on J was fabricated, which could act as a convenient and efficient Zn²⁺ test kit.     

Multi‐Level Logic Gate Operation Based on Amplified Aptasensor Performance

Conventional electronic circuits can perform multi‐level logic operations; however, this capability is rarely realized by biological logic gates. In addition, the question of how to close the gap between biomolecular computation and silicon‐based electrical circuitry is still a key issue in the bioelectronics field. Here we explore a novel split aptamer‐based multi‐level logic gate built from INHIBIT and AND gates that performs a net XOR analysis, with electrochemical signal as output. Based on the aptamer–target interaction and a novel concept of electrochemical rectification, a relayed charge transfer occurs upon target binding between aptamer‐linked redox probes and solution‐phase probes, which amplifies the sensor signal and facilitates a straightforward and reliable diagnosis. This work reveals a new route for the design of bioelectronic logic circuits that can realize multi‐level logic operation, which has the potential to simplify an otherwise complex diagnosis to a “yes” or “no” decision.     

Luminescent Carbon Dots for Logic Operations in Two Phases

Basic and higher integrated logic operations have been achieved by using luminescent carbon dots through interactions with metal ions and organic molecules in liquid dispersions as well as in the solid phase. The biphasic simple and complex logic systems could be potentially used for various analytical applications as well as for the detection of important elements in diverse environments.     

Recent Progress on the Development of Biofuel Cells for Self‐Powered Electrochemical Biosensing and Logic Biosensing: A Review

Biofuel cells (BFCs) based on enzymes and microorganisms have been recently received considerable attention because they are recognized as an attractive type of energy conversion technology. In addition to the research activities related to the application of BFCs as power source, we have witnessed recently a growing interest in using BFCs for self‐powered electrochemical biosensing and electrochemical logic biosensing applications. Compared with traditional biosensors, one of the most significant advantages of the BFCs‐based self‐powered electrochemical biosensors and logic biosensors is their ability to detect targets integrated with chemical‐to‐electrochemical energy transformation, thus obviating the requirement of external power sources. Following my previous review (Electroanalysis­ 2012 , 24, 197–209), the present review summarizes, discusses and updates the most recent progress and latest advances on the design and construction of BFCs‐based self‐powered electrochemical biosensors and logic biosensors. In addition to the traditional approaches based on substrate effect, inhibition effect, blocking effect and gene regulation effect for BFCs‐based self‐powered electrochemical biosensors and logic biosensors design, some new principles including enzyme effect, co‐stabilization effect, competition effect and hybrid effect are summarized and discussed by me in details. The outlook and recommendation of future directions of BFCs‐based self‐powered electrochemical biosensors and logic biosensors are discussed in the end.     

Finitary Topos for Locally Finite,Causal and Quantal Vacuum Einstein Gravity

The pentalogy (Mallios, A. and Raptis, I. (2001). International Journal of Theoretical Physics 40, 1885; Mallios, A. and Raptis, I. (2002). International Journal of Theoretical Physics 41, 1857; Mallios, A. and Raptis, I. (2003).International Journal of Theoretical Physics 42, 1479; Mallios, A. and Raptis, I. (2004). ‘paper-book’/research monograph); I. Raptis (2005). International Journal of Theoretical Physics (to appear)is brought to its categorical climax by organizing the curved finitary spacetime sheaves of quantumcausal sets involved therein, on which a finitary (:locally finite), singularity-free, background manifold independent and geometrically prequantized version of the gravitational vacuum Einstein field equations were seen to hold, into a topos structure . We show that the category of finitary differential triads is a finitary instance of an elementary topos proper in the original sense dueto Lawvere and Tierney. We present in the light of Abstract Differential Geometry (ADG) a Grothendieck-type of generalization of Sorkin’s finitary substitutes of continuous spacetime manifoldtopologies, the latter’s topological refinement inverse systems of locally finite coverings and their associated coarse graining sieves, the upshot being that is also a finitary example of a Grothendieck topos. In the process, we discover that the subobject classifier Ω _fcq of is a Heyting algebra type of object, thus we infer that the internal logic of our finitary topos is intuitionistic, as expected. We also introduce the new notion of ‘finitary differential geometric morphism’ which, as befits ADG, gives a differential geometric slant to Sorkin’s purely topological acts of refinement (:coarse graining). Based on finitary differential geometric morphisms regarded as natural transformations of the relevant sheaf categories, we observe that the functorial ADG-theoretic version of the principle of general covariance of GeneralRelativity is preserved under topological refinement. The paper closes with a thorough discussion of four future routes we could take in order to further develop our topos-theoretic perspective on ADG-gravity along certain categorical trends in current quantum gravity research. PACS numbers: 04.60.-m, 04.20.Gz, 04.20.-q Posted at the General Relativity and Quantum Cosmology (gr-qc) electronic archive (www.arXiv.org), as: gr-qc/0507100.     

On the <Emphasis Type="Italic">α</Emphasis>-superposition of functions of a <Emphasis Type="Italic">k</Emphasis>-valued logic

We reveal a relation between the operations of α-completion and closure for the systems of functions of a k-valued logic. For k = 3, 4 we construct the α-bases consisting of two binary operations. We prove that the complete system T of functions of a 4-valued logic containing all permutations of the set E ₄ = {0, 1, 2, 3} and the operation of addition modulo 4 is not α-complete, whereas its α-completion [T _α] will be an α-complete system.     

A Logic of Practical Reasoning

In this paper my primary aim is to present a logical system of practical reasoning that can be used to assess the validity of practical arguments, that is, arguments with a practical judgment as conclusion. I begin with a critical evaluation of other approaches to this issue and argue that they are inadequate. On the basis of these considerations, I explain in Sect. 2 the informal conception of practical validity and introduce in Sect. 3 the logical system P, which is an extension of propositional logic and can be used to assess the validity of a wide range of practical arguments. In the last section, I apply this system to some examples of practical reasoning in order to demonstrate how it can be used in practice.

Interval-type and affine arithmetic-type techniques for handling uncertainty in expert systems

Expert knowledge consists of statements _Sj$S_j$ (facts and rules). The facts and rules are often only true with some probability. For example, if we are interested in oil, we should look at seismic data. If in 90% of the cases, the seismic data were indeed helpful in locating oil, then we can say that if we are interested in oil, then with probability 90% it is helpful to look at the seismic data. In more formal terms, we can say that the implication “if oil then seismic” holds with probability 90%. Another example: a bank A trusts a client B, so if we trust the bank A, we should trust B too; if statistically this trust was justified in 99% of the cases, we can conclude that the corresponding implication holds with probability 99%.     

A review on the design of ternary logic circuits

A multi-valued logic system is a promising alternative to traditional binary logic because it can reduce the complexity, power consumption, and area of circuit implementation. This article briefly summarizes the development of ternary logic and its advantages in digital logic circuits. The schemes, characteristics, and application of ternary logic circuits based on CMOS, CNTFET, memristor, and other devices and processes are reviewed in this paper, providing some reference for the further research and development of ternary logic circuits.